1. Field of the Invention
The present invention relates in general to automotive vehicle doors and more particularly to a window door regulator for raising and lowering a door glass or window pane.
2. Description of the Prior Art
An X-arm type window regulator is widely used for an automotive vehicle frameless door as for example disclosed in the Japanese Provisional Utility Model Publication No. 54-3742 and includes a pair of front and rear guide rails arranged nearly vertically and secured to a door inner panel, a pair of guide rollers rotatably mounted on a door glass and movably received in the guide rails so that the door glass is movable upwardly and downwardly being guided by the guide rails, and an X-arm type drive unit by which the door glass is driven to move upwardly and downwardly.
In the prior art window regulator, the guide rails and the drive unit are formed as independent constituent parts or assemblies and separately mounted on a door panel by separate fastening means. Due to this, installation of the window regulator requires not only a difficult installation work but a delicate adjusting work, otherwise the door glass does not move smoothly.
Further, in the prior art window regulator, the point at which a driving force is transferred from the drive unit to the door glass traces a curved line upon movement of the door glass. Due to this, the door glass tends to swing forwardly and rearwardly to cause play of the guide rollers and the guide rails.